High Phosphates > 1,000 & High Nitrates 90ppm

I have a 26,000 gal pool with a salt generator. This is our 4th year and I suddenly can not keep chlorine in the pool. I have been using the BBB - putting in gallons of chlorine.

Latest test results:

Free Chlorine: .4 ppm
Total Chlorine: .8 ppm
Combined: .5 ppm
pH: 7.4
Hardness: 317
Alkalinity: 106
CYA: 58 ppm

PHOSPHATES: > 1,000
NITRATES: 90 PPM

I had a new sensor put in my salt generator, have boosted twice and am running at 70% and still can't keep chlorine!

So the recommendation is to drain the entire pool and re-fill with fresh water!

We are going away for a week, so I plan to add an algaecide, shock the heck out of it and run the system until we get back. Does this sound like the best approach?

Hi Apple;

Neither phosphates nor nitrates consume chlorine by themselves. They can promote algae . . . but without algae, they have ZERO effect on chlorine.

These things do:
+ Algae
+ Sunlight, in the absence of CYA
+ Sunlight -- even WITH CYA -- in the presence of sodium bromide (anything from United Chemical, various algae treatments fm others)
+ Yellow OUT, Mustard Master, and other ammonia based algae treatments
+ Bromine (tabs)
+ Ammonia from biodegradation of CYA (in spring or after a major algae bloom)
+ Urine, sweat, lotion from swimmers

Other things consume some chlorine, like most algaecides. But it's not a huge effect.

HOWEVER, it sounds like you are inferring chlorine loss from the fact that you've turned up your SWCG and have no chlorine. But, since you don't really know whether your SWCG is working properly, you don't actually know if there is chlorine in the pool to lose.

ALSO, your test numbers tell me you are getting results from some sort of digital reader, probably of test strips. These are typically quite inaccurate (even dealer models) and WILDLY unreliable.

SO, do this:

#1 - Get a cheap OTO / phenol red kit at Walmart and 12 gallons of *plain* 6% chlorine bleach.
#2 - This evening, within 2 hours of sunset, turn off your SWCG, add 6 gallons of bleach, and then test the water 1 hour after.
#3 - The following morning, within 2 hours of sunRISE, test again. If your results are DARK yellow, you probably have an SWCG problem, not a chlorine problem.
#4 - Test again that evening. If the chlorine has dropped a lot during the day, from the AM reading, you have low stabilizer AND a bogus testing process.

There are some other possibilities, so report your results here. Also, consider buy an K2006 or K2006C -- these are pretty much the cheapest reliable kits with a DPD-FAS chlorine test component.

Ben

Take a bucket of pool water and add chlorine to it. 1/4 teaspoon of 6% bleach in 2 gallons is 10 ppm FC. I'll bet you'll be able to have it register chlorine and hold it. If so, then you just haven't been adding enough to the pool and/or your chlorine generator may not be producing chlorine. You can take a water sample from the return when the SWCG is on to see if you register any chlorine.

It sounds like you've got nascent algae growth in the pool consuming the chlorine OR your SWCG isn't working.

Sorry I didn't get back to anyone - was having trouble logging on and then we were gone for a week. Happy to report that came home to a crystal clear pool - the chlorine level was very high 5.0!

Ok - I actually use both the OTO test kit and a K-2005 at home. The OTO shows plenty of chlorine but the k-2005 says it's low. (I will buy new kits today)

I took my water to two different pool companies. Yes, one used the digital test strips. The other used chemical drops. I am going to take water samples again today.

Both pool companies were telling me that it would be extremely difficult to maintain chlorine because of the phosphate and nitrate levels.

I will report back this afternoon.

Thank you

If you are going to be buying a new kit, why don't you get the one that we feel is the best which is the Taylor K-2006 or 2006C (same kit, larger bottle of some reagents). If you buy it through the Amazon link in my signature, the Pool Forum makes a little money on the sale which helps us keep this form online. Only buy if the seller is Amato Industries, however. Some other sellers are substituting the K-2005 which you do NOT want. Having this kit will make your pool maintenance much easier and you won't have to rely on pool stores for readings.

Quote:

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Originally Posted by applepar

Both pool companies were telling me that it would be extremely difficult to maintain chlorine because of the phosphate and nitrate levels.

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And, lemme guess, they had something to sell you to fix that?

Please, please post your K2005 test results . . . and please consider purchasing a K1515 DPD-FAS add-on for your K2005. (link to PoolSolutions page with links to items on Amazon, in my sig below)

Meanwhile, keep your chlorine high.

(By the way, I deleted your other posts asking the same question. Please ask once, in one place. It makes forums really really messy when people start asking their question in multiple places.)

In the blue table, underneath the moderators and my posts, are a group of links. One says "Amazon Links for FAS-DPD Kits".

Ben -- you beat me to it. I was also getting ready to find the other posts and delete them.

I also forgot about the add on part of the kit.

Applepar --- don't buy a whole K-2006 or 2006C. Just buy the K1515 kit. You have all the other parts of the K-2006 in your K2005 kit. That will give you the component that you are missing, but do need.

Regarding signatures ---- at the bottom of my post (and Ben's above) are some blue links. Click on the Amazon link and you'll find the K-1515 kit.

Today's readings with the k-2005 kit:

FC=1 Ph = 7.4
TC = 2 Bromine = 1
CC= 1 Alkalinity = 100
CYA = 65

I feel like an idiot, but I don't see any blue links at the bottom of any replies.

Still don't see blue links, but found it thru Pool Solutions.

Not your fault; mine, with help from vBulletin.

You should see more, now, plus get notifications on posts you've made.

Quote:

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Originally Posted by PoolDoc

Not your fault; mine, with help from vBulletin.

You should see more, now, plus get notifications on posts you've made.

---

Ben, I had to go into Settings and check mark view signatures in the Thread Display Options. I don't think I unchecked it last year--so maybe the default is unchecked? I did this a few weeks ago.

Quote:

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Originally Posted by applepar

Today's readings with the k-2005 kit:

FC=1 Ph = 7.4
TC = 2 Bromine = 1
CC= 1 Alkalinity = 100
CYA = 65

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1 ppm CC is good indication of a nascent algae bloom. This will consume all your chlorine
You are not using bromine so ignore the reading BUT if you are reading 1 on the bromine scale that is .5 on the chlorine scale so your chlorine readings are possibly off!

What kind of SWCG do you have? 65 is on the low end of where your CYA should be (higher CYA means slower pH rise for technical reasons so bump this up to the manufacturer's maximum)

100 is a bit high for TA in a salt pool and can lead to a higher acid demand because of more outassing of CO2. 70-80 ppm is better.
Also, maintain your pH at 7.6 instead of 7.4. The lower you put the pH the faster it rises (technical reason -- faster outgassing of CO2)

Phosphate and nitrate readings are generally bogus and are just used to sell (unneeded) phosphate remover products.

So I went to two pool places - different readings
First one uses BioGuard system - CYA = 96, Tot Chlorine = 1.3, Free Chlorine = .8, Ph = 7.7, Total Alkalinity 113, Total Hardness - 400
Phosphate test using paper tabs (way off from other tests = 20)
Told me that high nitrates can cause swimmers ear, rashes and pink eye (I had pink eye last week!)
Still recommend neutralizing the chlorine & draining and refilling the pool
Also to add ph down

The Second store used all drops in their testing Aqua - something
Free Chlorine = 1.7, Total Chlorine = 1.9, Combined Chlorine = = .3, pH = 7.9, Hardness = 338 ppm, Alkalinity = 93, CYA = 65
Phosphates was 1200, Nitrates = turned red in 30 seconds & by the end of the test was deep red
Before running the nitrates, they felt I was doing ok and could continue to run the salt system at 80% to get thru the season
After seeing the nitrate level they recommended that I drain the pool and replace the water as soon as possible
They said nitrates aren't harmful to people, but said recommendation is not to have babies & pregnant women swim

When I got home I am noticing a little green staining starting and it doesn't brush off. What is aa nascent algae bloom? And what do I do about it?

I have a Jandy AquaPure - last year i ran it between 35%- 60% depending on the heat, had no problems last year

I will adjust for the ph tonight and add bleach. I usually like the chlorine at 2.8.

Ben - I still need to do your suggestion to make sure the SWCG is working. I had taken a sample directly from the output and it was reading a higher chlorine, but if you think I should do the test you suggested at the beginning I will.

Thank you all for your continued help - I'm a frustrated fairly newbie pool owner!

Keeping your chlorine at 2.8 is an open invitation for algae to move in! Your CYA levels were reported as 96 and 65 which is a pretty big discrepancy. (Another good reason to get a good test kit and test it yourself.)

Chlorine levels depend on the CYA reading. If you keep your chlorine below the minimum needed, you'll get algae. Take a look at the Best Guess table in my signature below. To clear up this algae bloom, you need to raise your chlorine way up ("shock" the pool). This is another reason you'll need the good kit. Other test kits cannot measure high cl levels.

Please go back and re-read post #2 where Ben outlined what you need to do. I'm sure you are frustrated but if you follow the directions you are given here on the forum, we can help you take care of this. However, if you try and mix advice given here and advice given from a pool store or two, it will take much longer and be much more difficult.

This morning - Used my test kit K-2005 and once again very little chlorine

Free Chlorine = 1.0
Total Chlorine = 1.0
Combined Ch = 0

Based on the Best Guess Chart I should aim for at least a 5 correct?

So - my SWCG was set at 70% I took a sample right from the outlet and there was no difference in the readings


BTW - the documentation for my Jandy AquaPure recommends: FC 1-3, CC 0, CYA 50-75, pH 7.2-7.8, Alk 80-120


I also pulled out the 2 gallons of pool water and added 1/4 tsp of bleach and yes it read over 5 (I am letting it sit in the bucket to retest - is this what I should do?)

Next, I set my SWCG to Boost and tested from the outlet again and got a reading of at least 5


I added a gallon of bleach

What do you think?

I know I sound like a broken record but....I am concerned about the nitrate level and battling this chlorine problem.

In the Jandy documentation it says that Nitrates can cause extremely high chlorine demand and will deplete chlorine in the pool and may lower chlorine to zero. In addition, the EPA recommends no more than 10 ppm (mine was over 30), or can result in serious health risks to babies and pregnant women.

In previous posts (see below) the recommendation was to replace water or add borates.


Phosphate problems
Started by woody99‎, 06-28-2010
waterbear
Lifetime Member
Whibble Konker
If there is fertilizer run off from the golf course then nitrates are going to be a bigger problem for you than phosphates (and are also algae food) but nitrates are not normally tested for.
Do you know why?
There is no such thing as a nitrate remover. The only cure for high nitrates is water replacement with nitrate free water.

waterbear
Lifetime Member
Whibble Konker
Join Date
Nov 2004
Posts
2,995
Re: Leslie's says phosphates are way too high
Another way that is much easier than dealing with phosphate removers or montlhy additions of polyquat 60 is to add borates to your pool to 50 ppm.
You still need to maintain the proper FC/CYA relationship no matte which method you try.

Your problems are two-fold and obvious:
1) You need to raise your FC level to shock level, which, if I remember correctly is 20ppm, and KEEP IT THERE for several days. You have an algae bloom on the way. After that, IF you can establish that your SWCG is working you'll need to set it so your FC stays above 3.5ppm (if you have a CYA of 60-70). You are not keeping enough chlorine in your pool in relation to your CYA level to keep algae at bay and keep your water sanitary. IF it turns out your SWCG isn't functioning correctly, then you must MANUALLY maintain your FC in the 5-10ppm range--both are after shocking to kill everything.

2) You keep listening to the pool store and pool companies who are trying to sell you stuff, and, because you won't are pushing for drastic major action: "Oh, if you don't buy our special super-duper phosphate remover your only alternative is to drain and refill your pool!" NONSENSE! Your eyes and pinkeye aren't due to phosphates, they are due to insufficient chlorine unable to kill all the nasty stuff in your water it needs to kill. Your water is UNSANITARY. I, my fellow mods, our deeply experienced senior members, and our founder ALL told you what you need to do. You haven't done it.

It's just that simple. You need to add enough chlorine NOW to get the FC to 20ppm and you need to keep it there for several days.

And it is simple. Pool care is simple but pool companies and pool stores make their living out of keeping it complex. Fear trumps hope.

Carl

Wow! Believe it or not, no one put it as simply as you just did. I was just on my way to the store to buy bleach to shock the pool. I've spent all day researching and trying to figure out how much bleach I needed and what level is considered shock. I found a calculator on Trouble Free Pool that indicated I needed a level of 24-28 requiring 13 gallons of bleach.

I have ordered the add on testing kit as recommended.

So - what I'm hearing/reading is: I have algae that I can't see but is there and it is the cause of my chlorine disappearing. Once I get rid of the algae (by shocking) and keep my chlorine level up I should be ok. Won't I still need to keep the chlorine very high to keep algae from coming back?

What about the borate post?

Looks like I still have a problem with the SWCG. I contacted Jandy/Zodiac about the SWCG and this is what they said: Thank you for contacting Zodiac. Typical life span of the cell is 3-5 years. It sounds like the cell is reaching the end of its life span. You have a 5 year prorated warranty on the cell and can purchase a new one at a discounted rate from a dealer. Try increasing production until you can get a new cell put in.

By-the-way: The stores actually were not trying to sell the phosphate remover, because they said the nitrates were so extreme.

Actually some good questions:
"Shock" level is to kill the algae in your pool. That's the 20ppm you need--or higher.
But "Maintenance" level is what you need to KEEP your water sanitary. With a working SWCG, the level of chlorine should be NO LOWER than 5% of your CYA level. So if your CYA is 60, you need to keep at least 3ppm of chlorine for maintenance.

Here's a silly analogy: Say you have flying bugs in your house. You need to "bomb" the house to get rid of them. But once they are gone all you need to do is make sure your screens are well-fitted and not left open.

Borates is a whole different story. I wouldn't worry about them for now. Later, when you are comfortable with the basics, you can look into that. Some don't bother with borates (like me). Others do. There's no "right" answer just choices. You are OK without them for now.

The pool calculator works great but you can estimate too.
1 gallon of 6% bleach add 6ppm of free chlorine to 10,000 gallons of water. So, for your 26000 gallons (and it's probably really 25K) you need to use 2.5 gallons of 6% chlorine to get the same 6ppm. 5 gallons gets you to 12ppm. 10 gallons gets you to 24ppm (That's why I like Liquid Chlorine at 12.5%--you get the same effect from 5 gallons of LC 12.5% as you do from 10 gallons of 6% bleach.)

Carl

Thank you -
1. I haven't found 12.5% bleach anywhere - suggestions on where to find it?
2. Just went to Walmart & Lowe's looking for the recommended HtH Algaecide, but the HtH they have does not have the 60% Polyquat, so I didn't buy it. Sounds like you think I don't really need this? (Getting ready to try Leslie's or Anthony Sylvan.)

For now, just use plain 6% household bleach (no flavors, scents or gels, PLEASE). Just use 2x as much as you would pool bleach.

Regarding Walmart pool chemicals -- I hadn't checked them out for several years, till just the other day. Long story short: Walmart has gone over to the 'Dark Side' with their pool chemicals, and is totally a BioGuard / Chemtura mind-slave.

You can still buy 'bleach, borax and baking soda' there, and they now are selling "washing soda" = pH Up. But their algaecides and sanitizers are AWFUL.

I need to write a post about this, but I just haven't gotten around to it.